Rice Mexicana

Ingredients : 1 tablespoon vegetable oil 1 onion thinly sliced 1 green bell pepper thinly sliced 1 red bell pepper thinly sliced 1 (10.75 ounce) can condensed cream of mushroom soup ¼ cup milk 2 cups cooked white rice divided 1 cup shredded Monterey Jack cheese 6 (10 inch) heated...